Digital multimedia data such as video and music can be transmitted wirelessly to mobile receivers, such as wireless telephones, for playing of the multimedia by users of the mobile receivers. Such data typically may be broadcast.
In addition to the multimedia data itself, ancillary control data must also be provided to the receivers. This control data includes, e.g., decryption keys for decrypting the multimedia data, which may be encrypted to protect rights in the media. Also, the control data can include information related to a user's subscription to the broadcast, a user's registration for the broadcast service, billing information, and access control data.
Current methods for the wireless broadcast provision of digital media send the control data along with the multimedia data. As recognized herein, this reduces the amount of communication bandwidth that is available to carry the multimedia data, which tends to be bandwidth-intensive. Moreover, the present invention recognizes that sending, e.g., decryption keys along with the multimedia data to be decrypted by the keys poses security problems, even if mere possession of the keys, without more, is insufficient to easily decrypt the content. An unauthorized eavesdropper who intercepts the encrypted content also receives at least some information useful in decrypting it, and consequently is that much closer to pirating the content.